Grass Seed Calculator
Estimate how much grass seed your lawn needs for a new lawn or overseeding, from area and seed mix, in kilograms and pounds.
Seed needed (kilograms)
7
Breakdown
- Lawn area (m²)
- 200
- Application rate (g/m²)
- 35
- Seed needed (pounds)
- 15.43
- 15 kg bags to buy
- 1
- Approximate cost
- 0
Last updated:
FAQ
How much seed does a new lawn need?
About 35 g per m² — roughly one kilogram per 30 m². Overseeding an established lawn needs less (25 g/m²) because existing grass already covers part of the soil; patching worn spots seeds heaviest at ~45 g/m².
Can I put down too much seed?
Yes — seeds crowded together compete for light and moisture, and the weakest die off, wasting money and inviting fungus. Measure the area honestly and spread at the recommended rate rather than doubling up.
When is the best time to seed?
Cool-season grasses (fescue, ryegrass, bluegrass) establish best in early autumn when soil is warm but rain is reliable; warm-season varieties prefer late spring. Keep the top centimetre moist until germination finishes.
Related Calculators
Concrete Calculator
→Calculate cubic yards of concrete needed for a slab, footing or column, plus bags of 80lb mix and estimated cost.
Paint Calculator
→Estimate gallons of paint needed for your walls, with doors, windows and coats factored in.
Brick Calculator
→Estimate how many bricks you need for a wall, including a waste allowance.
Asphalt Calculator
→Estimate tons of hot-mix asphalt needed for a driveway or parking area.